Page 276 - Compression Machinery for Oil and Gas
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Screw Compressors Chapter 6 261
A
B
5
4 1 3
7
6 5 2 4 8
Key
A Inlet
B Outlet
1 Casing 5 Radial/thrust bearing
2 Male rotor 6 Timing gear
3 Female rotor 7 End cover
4 Shaft seal 8 Drive shaft
FIG. 6.6 Axial split dry screw. (From MAN Energy Solutions.)
Oil-Flooded Screw Compressors
Figs. 6.7 and 6.8 show sectional views of an oil-flooded screw compressor. In oil-
flooded screw compressors, sometimes referred to as oil-injected or wet screw
compressors, oil is injected directly into the rotor chamber continuously during
operation. The oil is discharged with the gas into an oil separator vessel and then
must be separated from the gas on the discharge side before being injected back
into the compressor again. The injection oil serves several purposes:
